1. Field of the Invention
The present invention relates to a oil filter, and more particularly, a drainable oil filter and method for draining oil from an engine.
2. Description of the Prior Art
Numerous innovations for oil filters with valve mechanisms have been provided in the prior art that will be described. Even though these innovations may be suitable for the specific individual purposes to which they address, however, they differ from the present invention.
A FIRST EXAMPLE, U.S. Pat. No. 3,235,085, Issued on Feb. 15, 1966, to Humbert Jr. teaches an oil filter comprising a casing with an inlet and outlet in one end thereof, a filter support member disposed adjacent the one end surrounding the outlet, a filter element supported on the member between the inlet and outlet for filtering oil flowed therebetween, port means in the member for communicating the inlet with the outlet, a slidable valve member extending between and blocking the port means and the outlet, biasing means maintaining the valve member seated over the inlet when oil ceases to flow through the inlet, the valve member having an area disposed to permit the pressure of oil entering the inlet to unseat it a sufficient distance from the inlet to permit normal filtering of oil, and the valve being disposed to permit a substantially higher oil pressure to act against a reduced portion of the area when the filter is clogged to unseat the valve a further distance from the inlet to open the port means to permit oil to bypass the filter element.
A SECOND EXAMPLE, U.S. Pat. No. 4,101,000, Issued on Jul. 18, 1978, to Scully teaches a mechanism for draining an engine oil filter cartridge when the space beneath the cartridge is otherwise obstructed. A special housing is threadably connected to the filter base in a non-obstructed location. A drain plug within this housing is manually unthreaded during a drain operation. A special boot in the mouth opening of the housing permits external actuation of the plug without undesired splash-out of oil through the mouth opening.
A THIRD EXAMPLE, U.S. Pat. No. 4,497,706, Issued on Feb. 5, 1985, to Pickett et al. teaches an oil filter relief valve having a tension spring housing with oil inlets and a first end and a second end, the first end being located adjacent the mounting plate of the filter, a base being fixedly connected to the second end of the spring housing and tension abutting and extending into the center tube of the filter element, a valve seat having a pointed surface and being located in the base with a channel formed therein for conducting oil therethrough, a resilient piston normally abutting the valve seat in sealing relation, a relatively rigid piston support on the piston, and a tension spring positioned between the first end of the tension spring housing and the piston support to urge the piston into sealing relation against the valve seat. This relief valve opens when the pressure of the oil entering the oil inlets and the channel in the valve seat exceed a particular threshold amount, thus exerting a force on the piston greater than the downward force naturally exerted by the spring. The piston is then lifted from the valve seat and the oil is allowed to flow through the relief valve and by-pass the filter element to immediately re-enter the motor.
A FOURTH EXAMPLE, U.S. Pat. No. 4,776,431, Issued on Oct. 11, 1988, to Poling teaches a method and apparatus for changing oil in an internal combustion engine that pierces an outer wall of an old oil filter containing old motor oil to form an opening in a lower portion of the filter wall. Old motor oil is drawn from the pierced oil filter into a container by suction through the filter wall opening and a suction conduit. The oil drain plug from a crankcase containing old motor oil is removed to form a drain opening in the crankcase, and old motor oil is drawn from the crankcase into a container by suction through the drain opening and a suction cup, to empty the crankcase of old motor oil. The drain opening is closed after emptying the crankcase of old motor oil by securing the drain plug in the drain opening. The pierced and drained old oil filter is replaced with a new filter and the drained crankcase is refilled with fresh motor oil.
A FIFTH EXAMPLE, U.S. Pat. No. 4,872,976, Issued on Oct. 10, 1989, to Cudaback teaches an elastomeric valve member which coacts with a valve seat and an apertured plate to control the flow of oil between the inlet and outlet of an oil filter for an internal combustion engine. When the engine is shut down, the valve member seals against both the valve seat and the plate to hold oil in the filter and prevent such oil from returning to the crankcase via the inlet. Under normal running conditions, the valve member unseals with respect to the plate to permit oil to flow between the inlet and outlet by way of the filter element of the filter. If the pressure differential between the inlet and the outlet exceeds a predetermined value, the valve member unseals with respect to the valve seat to enable the oil to bypass the filter element and to flow directly from the inlet to the outlet.
A SIXTH EXAMPLE, U.S. Pat. No. 5,250,176, Issued on Oct. 5, 1993, to Daniel teaches a modular compound valve assembly for an automotive oil filter that includes a relief valve subassembly and a clean-side anti-drainback valve subassembly sharing a common unitary valve body. In one preferred form, the valves body is formed of a stepped cylinder, wherein axially opposed surfaces of a first step comprise respective seats for first and second springs utilized in the two valve subassemblies. The first spring (for the relief valve) is entirely contained within the valve body, while the second spring (for the anti-drainback valve) is external to the valve body although supported thereon. The second spring is a frustoconically-shaped spring biased between the first step of the valve body and an external circular disc spaced from but fixed to a plunger of the anti-drainback valve. To the extent that the anti-drainback plunger is adapted for being seated within the valve body, the compound valve assembly offers greater flexibility in stocking inventories of valve subassemblies for in-field selection and modification. For example, the anti-drainback valve subassembly may be “piggybacked” onto the relief valve subassembly without requirement of special tools. Finally, in the same preferred form, the anti-drainback subassembly includes a pair of struts fixed to the circular disc, wherein the second spring is maintained under constant compression between the disc and step of the valve body to close the anti-drainback plunger, and hence to avoid leakage of clean oil from the filter, upon shutdown of an associated engine.
A SEVENTH EXAMPLE, U.S. Pat. No. 6,488,845, Issued on Dec. 3, 2002, to Neufeld et al. teaches an oil filter assembly which includes a filter housing and a release valve for regulating oil drainage from a filter chamber in the filter housing. A filter module is arranged in the filter chamber to engage the release valve. A first biasing element normally moves the release valve to an opened position allowing drainage of oil from the filter chamber to urge the filter module to cause the release valve to move against and overcome a biasing force generated by the first biasing element to the closed position when the filter module is installed in a oil-filtering position in the filter housing.
It is apparent now that numerous innovations for oil filters with valve mechanisms have been provided in the prior art that adequate for various purposes. Furthermore, even though these innovations may be suitable for the specific individual purposes to which they address, accordingly, they would not be suitable for the purposes of the present invention as heretofore described.